FR2664106A1 - DIRECT CURRENT ELECTRIC DRIVE MOTOR FOR MOTOR VEHICLE. - Google Patents

Abstract

The present invention relates to a direct current electric traction motor. The motor is characterized in that it comprises at least one flange (17; 18) integral with the motor shaft (6) and provided with means (19, 20, 21) for centering and holding the pack (7) of rotor plates, the flange (17; 18) and the centering and holding means (19, 20, 21) being arranged relative to the motor shaft (6) so as to leave in the housing (2) a space (E ) for housing a reduction gear or an electromagnetic clutch. The present invention finds application in electric vehicles.

Description

1 - The present invention relates to an electric traction motor with

  direct current intended in particular for a

motor vehicle.

  The problem that currently arises for electric motor vehicles is their mass In fact, these vehicles must carry a large mass of electric motor power batteries to achieve satisfactory performance It is therefore necessary to perform work of lightening of electric vehicles in order to extend their range and their acceleration capabilities in spite of the power of the electric motor unchanged These lightenings relate to all the components of the vehicle and

  particular on the engine of it.

  FIG. 1 shows a conventional electric motor consisting of a rotor assembly R, a stator assembly S, a collector assembly CO and brushes B with the drive shaft A supporting the rotor assembly R held by two bearings P casings C by means of ball bearings RB According to this known motor, the coupling with a device such as a gearbox can only be realized outside the casing C, which imposes a space requirement in fairly large length compatible with a mount on

an electric vehicle.

  The present invention thus provides an electric traction motor designed to lighten the motor vehicle equipped with such a motor while allowing a reduction in the assembly time and especially a reduction of

  the overall length of the engine.

  For this, the electric traction motor according to the invention, of the type comprising a stator assembly secured to a housing, a rotor assembly integral with the motor shaft comprising a contiguous rotor sheet package and a collector-brush assembly, is characterized in that it comprises at least one flange secured to the drive shaft and provided with centering and holding means 2 - rotor plates coaxially with the drive shaft and in that the flange and the centering means and maintenance are arranged relative to the drive shaft so as to arrange in the housing, concentrically to the drive shaft, a space for housing a coupling device,

  such as a reducer or an electromagnetic clutch.

  According to a characteristic of the invention, the output shaft of the aforementioned coupling device is mounted coaxially with the axis of the motor shaft and passes through the latter in the form of a cylindrical sleeve of relatively short length mounted on the side of the together

  brush manifold opposite the aforementioned space.

  According to another characteristic of the invention, in the case of a gearbox as a coupling device, a differential is coupled to the gearbox and housed in the aforementioned space with the aforementioned output shaft and a second output shaft of the gearbox. forming a double

axial output.

  According to a first embodiment, the centering and holding means comprise a cylindrical tube fixed on the aforementioned flange and supporting the annular disk-shaped rotor plates and two end flanges of the cylindrical tube enclosing the

rotor plates.

  Advantageously, the flange located on the side of the aforementioned brushes is connected to a cylindrical tip in which is fixed, by fitting either shrunk or glued, a cylindrical sleeve support of the aforementioned collector, the

flat type.

  According to another characteristic of the invention, two parallel flanges, integral with the drive shaft, are provided and the aforementioned cylindrical tube of preformed sheet is fixed on the two flanges by welding. According to a second embodiment, the centering and holding means comprise a number of 3-screws or tie rods for fixing the annular disk-shaped rotor plates to the aforementioned flange and passing through the package of rotor plates and the flange coaxially to

the axis of the motor shaft.

  The aforementioned fixing screws or tie rods are screwed into a cylindrical support sleeve of the flat-type collector and acting as a clamping nut for the rotor plates. According to a third embodiment, the above-mentioned centering and holding means comprise a number of through rods that secure the package of rotor plates to the flange by their crimped ends which also hold a cylindrical support endpiece.

of the collector.

  The invention will be better understood and other purposes, features, details and advantages thereof

  will become clearer during the description

  explanatory text which will follow with reference to the accompanying schematic drawings given solely by way of example illustrating several embodiments of the invention and in which: Figure 1 shows in longitudinal section a conventional electric traction motor; FIG. 2 shows in longitudinal half-section an electric motor according to a first embodiment; FIG. 3 is a longitudinal half-section showing an electric motor according to a second embodiment of the invention; and Figure 4 is a longitudinal sectional view of an electric motor in which is incorporated a gear-differential assembly. Referring to FIG. 2, the DC traction electric motor intended in particular for a motor vehicle comprises a stator assembly 1 integral with the cylindrical casing 2 of the motor, with an excitation winding 3 and a pack 4 with stator plates. joined in the form of annular discs (the stator may also be square, hexagonal), a rotor assembly 5 integral with the drive shaft 6 and consisting of a bundle 7 contiguous rotor plates in the form of annular disks on which is wound a winding 8 and a collector assembly 9-brushes 10 The brushes 10 are slidably mounted in brush holders 11 secured to a radial wall 2a for closing the housing 2 and held elastically in electrical contact with the collector 9 as symbolized in 12L 6 is held by two bearings 13 and 14 respectively to the radial walls 2a and 2b closing the housing 2 via

ball bearings 15 and 16.

  According to the invention, the electric motor further comprises two parallel flanges 17, 18 secured by

  example by welding, the motor shaft 6 perpendicular-

  to the latter and provided with means for centering and maintaining the package of rotor plates 7 coaxially with the longitudinal axis of the drive shaft 6 These centering and holding means comprise a cylindrical tube 19 fixed for example by welding on the two flanges 17 and 18 and supporting the package of rotor plates 7 and two end flanges 20 and 21 of the tube 19 enclosing the rotor plates of the package 7 The flanges 17, 18 are positioned relative to the shaft 6 and the tube 19 has a diameter internal manner so as to define or arrange a space E for housing a coupling device such as a reducer possibly associated with a differential or an electromagnetic clutch The tube 19 is made by preforming a sheet and the flanges 17, 18 may be contiguous or constitute a single flange, whose positioning relative to the shaft 6 is formed by a shoulder 6a of the latter The collar 20 located on the side brushes 10 is connected to a cylindrical end piece 22 in which is fixed for example by fitting either fr 8tte or glued, a cylindrical sleeve 23 of the collector support 9 in the form of annular ring flat face electrical contact with the brushes 10 The sleeve 23 is secured to the collector 9 by a dolphin-shaped dovetail 9 a-mortise fastener 9a with interposition between the pin 23a and the mortise 9a of a

electrical insulation 24.

  The method of assembling the rotor assembly 5 and the

  collector 9 to tube 19 results from the description that was

  made above and need not be more detailed except that the rotor plates of the package 7 are threaded contiguously on the tube 19 and positioned axially by the radial flange 20 forming a positioning stop and, once all the rotor plates are threaded, the flange 21 is formed by folding the corresponding end of the tube 19 against the last rotor sheet

  opposed to that abutting on the flange 20.

  According to the second embodiment of the electric motor shown in FIG. 3 or the parts common to those of FIG. 2 and of identical structure bear the same references, a flange 25 secured for example by welding the drive shaft 6 and positioned relatively to the latter by the shoulder 6a, carries the pack 7 of annular disc shaped rotor plates centered coaxially with the shaft 6 by tie rods or fixing screws 26 passing through the package 7 and the flange 25 coaxially to the shaft The flange 25 is shown arranged to be clamped approximately between two half-packs of rotor plates, but it is obvious that it can be positioned relative to the shaft 6 so as to be located to the left of the FIG. 3 to define an even larger space E housing a reducer possibly associated with a differential or an electromagnetic clutch This space E is ain if defined by the flange 25, the internal diameter of the rotor plates, the internal diameter of the winding 8 and the wall 2b The tie rods or fixing screws 26 have their opposite ends r 6 - the retaining heads of the rotor plates which are screwed into the cylindrical sleeve 23 of the collector support 9, which sleeve thus acts as a clamping nut and

  holding the rotor plates to the flange 25.

  FIG. 4 represents the integration of a mechanical device in the space or housing E and constituted by a gear 27 mechanically coupled to the drive shaft 6 of the electric motor and by a differential 28 mechanically coupled to the gearbox 27 so as to drive together the two output shafts 29 and 30 each carrying a wheel of the vehicle at angular speeds which can differ freely The two output shafts 29 and 30 thus constitute a double axial output of the gear 27 and the output shaft 30 is coaxially mounted in the tubular shaft 6 of relatively short length mounted on the side of the collector assembly 9-brushes 10 opposite the space E in

  which is housed the 27-differential gear unit 28.

  Of course, the output shaft 30 is rotatably mounted in the shaft 6 via a needle bearing 31 while the output shaft 29 is rotatably mounted relative to a support bearing constituted by a cover 32 closing the space E via a needle bearing 33, the cover 32 being fixed by means of fixing screws 34 to the housing 2 of the electric motor The structure and operation of the gearbox 27 and the differential 28 being known per se, they do not have to be further detailed In the case of an electric motor per vehicle wheel, only the reducer 27 will be provided in the space E and it is clear that it is possible to

  instead of the gear reducer 27, provide an electronic clutch

Magnetic as needed.

  FIG. 4 represents in fact two different half-views where the upper half-life is similar to the embodiment of fastening of the rotor laminations of the pack 7 represented in FIG. 3 and the lower half-view corresponds to the embodiment of FIG. Referring to the upper half-view of FIG. 4, it will be noted that the assembly and centering of the pack 7 of rotor laminations to the flange 25 is carried out by through rods 35 coaxial with the drive shaft 6 and holding the rotor plates. The crimped end of the side of the collector 9 also holds a cylindrical end piece 36 corresponding to the end piece 22 of FIG. 2 and on which is attached, for example by fitting either a fretted or glued joint, a cylindrical sleeve 37 of support of the collector 9, the assembly of the sleeve 37 to the collector 9 being identical to that shown in Figures 2 and 3 The upper half-view also shows the presence of a flask conduction 38 parallel to the flange 25, secured by welding of the shaft 6, and clamped by crimped end of the rod 35 between the package of rotor plates and a radial portion connected to the tip 36 The embodiment of the half 4 is identical to that of FIG. 2, it does not have to be described with the only difference, as for the upper half-view, that the flanges 17, 18 and the flange 25 are closer to the 9, the collector 9 with respect to FIGS. 2 and 3 so as to enlarge the housing E. The electric motor of the invention as represented in FIGS. 2 to 4 thus solves the problem of length congestion by being arranged so as to be able to implant therein a reducer possibly associated with a differential or an electromagnetic clutch In addition to the decrease in the overall length, the proposed assembly of the electric motor allows both a lightening

and a reduced assembly time.

8 -

Claims (8)

R E V E N D I C A T I ONS   1 DC electric traction motor intended in particular for a motor vehicle comprising a stator assembly (1) integral with a housing (2), a rotor assembly (5) integral with the drive shaft (6) comprising a package (7) ) contiguous rotor plates and a collector assembly (9) -balais (10), characterized in that it comprises at least one flange (17, 18; 25) integral with the drive shaft (6) and provided with means ( 19, 20, 21, 26, 35) for centering and holding the rotor plates coaxially with the drive shaft (6) and in that the flange (17, 18; 25) and the means (19, 20, 21; 35) are arranged relatively to the drive shaft (6) so as to arrange in the housing (2), concentrically with the drive shaft (6), a space (E) for accommodating a coupling device   such as a reducer (27) or an electromagnetic clutch.   Electric motor according to Claim 1, characterized in that the output shaft (30) of the aforementioned coupling device (27) is mounted coaxially with the axis of the shaft (6) and passes through the motor shaft ( 6) in the form of a cylindrical sleeve of relatively short length mounted on the side of the collector assembly (9) -balans (10) opposite to the space (E) above.   3 Electric motor according to claim 2, characterized in that it also comprises, in the case of a gearbox (27) as a coupling device, a differential (28) coupled to the gearbox (27) and housed in the space (E) cited above with the aforementioned output shaft (30) and a second output shaft (29) of the reducer (27) forming a double axial output.   Electric motor according to one of the preceding claims, characterized in that the centering means   and said holding means comprise a cylindrical tube (19) fixed on the flange (17, 18) and supporting the pack (7) rotor-shaped plates in the form of annular disks and 9-9- two end flanges (20, 21) of the cylindrical tube (19) enclosing the rotor plates.   Electric motor according to one of the claims   previous, characterized in that the collar (20) on the side of the brushes (10) above is connected to a cylindrical tip (22) in which is fixed for example by fitting either shrunk or glued, a cylindrical sleeve (23). support of the above-mentioned collector (9), flat type.   Electric motor according to one of the claims   preceding, characterized in that it comprises two parallel flanges (17, 18) integral with the drive shaft (6) and in that the cylindrical tube (19) above, preformed sheet metal,   is fixed on the two flanges (17, 18) by welding.   Electric motor according to one of claims 1   at 3, characterized in that the above-mentioned centering and holding means comprise a number of screws or tie-rods (26) for fixing the packet (7) of annular disk-shaped rotor plates to the above-mentioned flange (25) and passing through the package (7) of rotor plates and flange   (25) parallel to the axis of the motor shaft (6).   8 electric motor according to claim 7, characterized in that the screws or tie rods (26) above are screwed into a cylindrical sleeve (23) of the support of the collector (9) of the flat type and making office   nut clamping the rotor plates of the package (7).   Electric motor according to one of claims 1   at 3, characterized in that the above-mentioned centering and holding means comprise a number of through rods (35) which secure the package (7) of rotor plates to the flange (25) by their crimped ends which also hold a cylindrical end ( 36) of collector support (9).